SINGAPORE, Aug 11 (Reuters) – The dollar skidded to an eight-week low against the yen on Friday as escalating tensions between the United States and North Korea triggered yet more investor flight to safety.

The dollar last changed hands at 108.96 yen , down 0.2 percent. Trading was thinner than usual, with Japanese markets closed for a public holiday.

Earlier, the dollar slipped as low as 108.91 yen, its weakest level since June 14, when the greenback fell as low as 108.81 yen.

Below that level lies another key technical chart support level for the dollar at 108.13 yen, a trough the U.S. currency k plumbed in mid-April.

“We’re getting close towards very important support on the dollar/yen,” said Steven Dooley, currency strategist for Western Union Business Solutions in Melbourne.

“Particularly that 108.10/108.00 level, a break below those levels would really set up a rapid move to the downside,” he said.

Both the Swiss franc and the yen have climbed against the dollar this week, after U.S. President Donald Trump warned North Korea that it would face “fire and fury” if it threatened the United States.

Trump ratcheted up his rhetoric against North Korea and its leader on Thursday, warning Pyongyang against attacking Guam or U.S. allies after it disclosed plans to fire missiles over Japan to land near the U.S. Pacific territory. The Swiss franc has gained about 1.3 percent against the dollar so far this week, while the yen has advanced around 1.5 percent in the same period.

The Swiss franc and Japanese yen are often sought in times of geopolitical tension or global financial stress, partly because both countries have big current account surpluses.

Japan is the world’s biggest creditor nation and there is an assumption Japanese investors may repatriate their foreign holdings in times of heightened global uncertainty.